A fluorohydrocarbon compound exhibits excellent etching selectivity with respect to the etching target material, and has been used in recent years as a dry etching gas for producing a semiconductor device.
A fluorohydrocarbon compound that is used in the semiconductor production field and the like is required to have a reduced water content in order to achieve high etching selectivity.
A fluorohydrocarbon compound may be dehydrated using a molecular sieve (hereinafter may be referred to as “MS”) that is a common dehydrating agent.
However, isomerization and a decomposition reaction easily occur when a fluorohydrocarbon compound is brought into contact with an MS, whereby the purity of the fluorohydrocarbon compound decreases.
In order to solve this problem, Patent Literature 1 discloses a method for purifying a fluorohydrocarbon compound that includes bringing a specific crude fluorohydrocarbon compound into contact with a hydrous metal salt of a synthetic crystalline aluminosilicate having an average pore size of 3 Å to remove water from the crude fluorohydrocarbon compound, for example.